GB752882A - Improvements in or relating to thread winding machines and methods of operating such machines - Google Patents

Abstract

752,882. Thread winding machines. REINERS, W. Nov. 20, 1953 [Nov. 20, 1952], No. 32332/53. Class 120 (2). In a method of controlling a thread winding machine of the kind having a predetermined maximum limiting power input or supply, and one or more non-continuous and at least partly independent working operations, before any such working operation is begun an assessment is made as to whether sufficient power and/or energy is available for the operation to be completed, and the commencement of this and any other working operation is prevented if insufficient power and/or energy is available for its completion. The working operations may be, for example, bobbin changing, thread knotting, marking, &c. and the assessment of the power or energy available may be made by subtracting or comparing the total power being used at any instant from or with the total power available. This may be done by reference to the pressure in a suction accumulator, by the current in the electric supply to the driving motor or by the flow in an air suction pipe to the machine driving means. Alternatively, instead of using actual power values component factors or substitution values, i.e. values which are proportional to the actual power values may be used. These latter values may be electrical, pneumatic or hydraulic resistances or photoelectric cells. A machine operating according to the above method may include control means arranged to enable the drive for each working operation to be initiated only at stated intervals and check means arranged to render the control means inoperative when insufficient power or energy is available so as to prevent any further working operation being initiated. In the arrangement shown in Fig. 1, 30 is a control shaft on which is mounted a series of spaced cams 109 staggered at equal angles. The shaft 30 is driven through a slip coupling 34 and has a ratchet wheel 114 mounted thereon which is arranged to be engaged by a pawl 113 on one end of a bell-crank lever 112, the other end of which is connected to a diaphragm 111 arranged in a wall of a suction accumulator 102 and the arrangement is such that when the pressure in the accumulator falls below a predetermined value the pawl 113 engages the ratchet wheel 114 and thus prevents further rotation of the shaft 30. Each cam 109 co-operates with a rocker arm 20 which is connected through the compression spring 21 to a push-rod 19. The push-rods 19 are each connected to the control element of a clutch or other transmission device by which power may be transmitted to mechanism for carrying out some working operation. It will be seen that since the control shaft 30 is normally rotated continuously the push-rods are lifted successively to permit the initiation of the working operations. If, however, due to an indication that there is insufficient power available the shaft 30 is held by means of the pawl 113, no further working operation will be initiated. Further interlocks are provided in the drive to each working operation and arranged to be responsive to some predetermined operating condition for example thread breakage or an empty bobbin &c. In other embodiments the pawl 113 is operated by a solenoid in the supply circuit to the driving motor of the machine; by a flow responsive valve arranged in an air supply pipe and by a solenoid in an electric circuit into which electric resistances are connected whenever a working operation is in progress so that the current in the circuit gives an indication of the power being consumed at any instant and when this reaches a predetermined value in relation to the known and maximum value the pawl is operated by the solenoid to prevent the initiation of any further working operations. Specification 752,872 is referred to.